Casimir I of Oświęcim

Casimir I of Oświęcim (Polish: Kazimierz I Oświęcimski) (1396 – 7 April 1434) was a Duke of Oświęcim since 1406 (under regency until 1414), ruler over Toszek (from 1414) and Strzelin (during 1416–1427).

He was the only child of Duke Przemysław of Oświęcim by his unknown wife.

After his father's death on 1 January 1406, Casimir I was placed under the care of his paternal grandfather, Duke Przemysław I Noszak of Cieszyn, and, after his death in 1410, his guardianship was taken by his uncle Bolesław I.

On 19 December 1414 Casimir I took formal possession of his Duchy of Oświęcim, along with the towns of Toszek and Gliwice. However, the ambitions of the young Duke erupted then and claimed more lands from his uncle. The conflict ended only two years later, on 11 November 1416 when (following the mediation of Duke Henry IX of Lubin), the Duke of Cieszyn give the town of Strzelin and 300 fines as payment to Casimir I. Bolesław I retained the rest of his lands.

In 1424 Casimir I took part in the coronation of Sophia of Halshany as Queen of Poland. However, this doesn't mean that the Duke of Oświęcim maintain a pro-Polish politics; in fact, he began at the same time his contacts to with the Bohemian King Sigismund of Luxembourg, and even spend some time in his court (there are information that Casimir I, for unknown reasons, received from the King a pension for 3,000 pieces of gold, perhaps as a payment for his mediation with the Teutonic Order, which, had good relations with the Duke of Oświęcim).

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